Extra Tags

The extra tags represent extra information extracted or generated by
ExifTool that is not directly associated with another tag group. The
Group column lists the family 1 group name when reading. Tags with a "-"
in this column are write-only.

Tags in the family 1 "System" group are referred to as "pseudo" tags because
they don't represent real metadata in the file. Instead, this information
is stored in the directory structure of the filesystem. The five writable
"pseudo" tags (FileName, Directory, FileModifyDate, FileCreateDate and
HardLink) may be written without modifying the file itself. The TestName
tag is used for dry run testing of writes to FileName.

Tag Name

Writable

Group

Values / Notes

Adobe

Y!

Adobe

(the JPEG APP14 Adobe segment. Extracted only if specified. See the
JPEG Adobe Tags for more information)

CanonDR4

Y!

CanonVRD

(the full Canon DPP version 4 DR4 block)

CanonVRD

Y!

CanonVRD

(the full Canon DPP VRD trailer block)

Comment

Y

File

(comment embedded in JPEG, GIF89a or PPM/PGM/PBM image)

CurrentIPTCDigest

N

File

(MD5 digest of existing IPTC data. All zeros if IPTC exists but Digest::MD5
is not installed. Only calculated for IPTC in the standard location as
specified by the MWG. ExifTool
automates the handling of this tag in the MWG module -- see the
MWG Composite Tags for details)

Directory

Y!

System

(the directory of the file as specified in the call to ExifTool, or "." if no
directory was specified. May be written to move the file to another
directory that will be created if doesn't already exist)

EXIF

Y!

EXIF

(the full EXIF data block from JPEG, PNG, JP2, MIE and MIFF images)

Error

N

ExifTool

(returns errors that may have occurred while reading or writing a file. Any
Error will prevent the file from being processed. Minor errors may be
downgraded to warnings with the -m or IgnoreMinorErrors option)

ExifByteOrder

Y

File

(represents the byte order of EXIF information. May be written to set the
byte order only for newly created EXIF segments)'II' = Little-endian (Intel, II)
'MM' = Big-endian (Motorola, MM)

ExifToolVersion

N

ExifTool

(the version of ExifTool currently running)

ExifUnicodeByteOrder

Y

-

(specifies the byte order to use when writing EXIF Unicode text. The EXIF
specification is particularly vague about this byte ordering, and different
applications use different conventions. By default ExifTool writes Unicode
text in EXIF byte order, but this write-only tag may be used to force a
specific order)'II' = Little-endian (Intel, II)
'MM' = Big-endian (Motorola, MM)

FileAccessDate

N

System

(the date/time of last access of the file. Note that this access time is
updated whenever any software, including ExifTool, reads the file)

(extracted only if specifically requested or the SystemTags API option is set)

FileBlockSize

N

System

(extracted only if specifically requested or the SystemTags API option is set)

FileCreateDate

Y!

System

(the filesystem creation date/time. Windows only. Requires Win32API::File
and Win32::API for writing. Note that although ExifTool can not currently
access the filesystem creation time on other systems, the creation time is
pushed backwards on OS X by writing an earlier modification time, which
provides a mechanism to write this indirectly: 1) Rewrite the file to set
the filesystem creation and modification times to the current time, 2) Set
FileModifyDate to the desired creation time, then 3) Restore FileModifyDate
to its original value)

FileDeviceID

N

System

(extracted only if specifically requested or the SystemTags API option is set)

FileDeviceNumber

N

System

(extracted only if specifically requested or the SystemTags API option is set)

FileGroupID

N

System

(extracted only if specifically requested or the SystemTags API option is set)

FileHardLinks

N

System

(extracted only if specifically requested or the SystemTags API option is set)

FileInodeChangeDate

N

System

(the date/time when the file's directory information was last changed.
Non-Windows systems only)

FileInodeNumber

N

System

(extracted only if specifically requested or the SystemTags API option is set)

FileModifyDate

Y!

System

(the filesystem modification date/time. Note that ExifTool may not be able
to handle filesystem dates before 1970 depending on the limitations of the
system's standard libraries)

FileName

Y!

System

(may be written with a full path name to set FileName and Directory in one
operation. This is such a powerful feature that a TestName tag is provided
to allow dry-run tests before actually writing the file name. See
filename.html for more information on writing the
FileName, Directory and TestName tags)

(r=read, w=write and x=execute permissions for the file owner, group and
others. The ValueConv value is an octal number so bit test operations on
this value should be done in octal, eg. 'oct($filePermissions#) & 0200')

FileSequence

N

ExifTool

(sequence number for each source file when extracting or copying information,
including files that fail the -if condition of the command-line application,
beginning at 0 for the first file. Not generated unless specifically
requested)

(a short description of the file type. For many file types this is the just
the uppercase file extension)

FileTypeExtension

N

File

(a common lowercase extension for this file type, or uppercase with the -n
option)

FileUserID

N

System

(extracted only if specifically requested or the SystemTags API option is set)

Geosync

Y

-

(this write-only tag specifies a time difference to add to Geotime for
synchronization with the GPS clock. For example, set this to "-12" if the
camera clock is 12 seconds faster than GPS time. Input format is
"[+-][[[DD ]HH:]MM:]SS[.ss]". Must be set before Geotime to be effective.
Additional features allow calculation of time differences and time drifts,
and extraction of synchronization times from image files. See the
geotagging documentation for details)

(this write-only tag is used to define a date/time for interpolating a
position in the GPS track specified by the Geotag tag. Writing this tag
causes GPS information to be written into the EXIF or XMP of the target
files. The local system timezone is assumed if the date/time value does not
contain a timezone. May be deleted to delete associated GPS tags. A group
name of 'EXIF' or 'XMP' may be specified to write or delete only EXIF or XMP
GPS tags. The Geotag tag must be assigned before this tag)

HardLink

Y!

-

(this write-only tag is used to create a hard link to the file. If the file
is edited, copied, renamed or moved in the same operation as writing
HardLink, then the link is made to the updated file. Note that subsequent
editing of either the linked file or the original by the exiftool
application will break the link unless the -overwrite_original_in_place
option is used)

ICC_Profile

Y!

ICC_Profile

(the full ICC_Profile data block)

ID3Size

N

File

(size of the ID3 data block)

IPTC

Y!

IPTC

(the full IPTC data block)

ImageHeight

N

File

(the height of the image in number of pixels)

ImageWidth

N

File

(the width of the image in number of pixels)

JPEGDigest

N

File

(an MD5 digest of the JPEG quantization tables is combined with the component
sub-sampling values to generate the value of this tag. The result is
compared to known values in an attempt to deduce the originating software
based only on the JPEG image data. For performance reasons, this tag is
generated only if specifically requested)

(the current date/time. Useful when setting the tag values, eg.
"-modifydate<now". Not generated unless specifically requested)

PreviewImage

Y

File

(JPEG-format embedded preview image)

PreviewPNG

N

File

(PNG-format embedded preview image)

PreviewWMF

N

File

(WMF-format embedded preview image)

ProcessingTime

N

ExifTool

(the clock time in seconds taken by ExifTool to extract information from this
file. Not generated unless specifically requested. Requires Time::HiRes)

RAFVersion

N

File

(RAF file version number)

ResourceForkSize

N

System

(size of the file's resource fork if it contains data. Mac OS only. If this
tag is generated the ExtractEmbedded option may be used to extract
resource-fork information as a sub-document. When writing, the resource
fork is preserved by default, but it may be deleted with -rsrc:all= on
the command line)

TestName

Y

-

(this write-only tag may be used instead of FileName for dry-run tests of the
file renaming feature. Writing this tag prints the old and new file names
to the console, but does not affect the file itself)

Warning

N

ExifTool

(returns warnings that may have occurred while reading or writing a file.
Use the -a or Duplicates option to see all warnings if more than one
occurred. Minor warnings may be ignored with the -m or IgnoreMinorErrors
option. Minor warnings with a capital "M" in the "[Minor]" designation
indicate that the processing is affected by ignoring the warning)

XMP

Y!

XMP

(the XMP data block, but note that extended XMP in JPEG images may be split
into multiple blocks)